Abstract: An optically-monitored and/or optically-controlled electronic device is described. The device includes at least one of a semiconductor transistor or a semiconductor diode. An optical detector is configured to detect light emitted by the at least one of the semiconductor transistor or the semiconductor diode during operation. A signal processor is configured to communicate with the optical detector to receive information regarding the light detected. The signal processor is further configured to provide information concerning at least one of an electrical current flowing in, a temperature of, or a condition of the at least one of the semiconductor transistor or the semiconductor diode during operation.

Abstract: A pyramid-type multilevel converter for converting DC voltage to AC voltage waveforms, and vice versa. An example device can use modular building blocks to form a selector stage, a converter stage, and at least one intermediate stage if the number of converters within the converter stage is greater than or equal to 3, with the converter stage switching at high-frequency PWM to chop the DC voltages. The modular building blocks are connected in a symmetric or asymmetric pyramid configuration having a base of using the converter stage and an apex of the selector stage.

Abstract: An optically-monitored and/or optically-controlled electronic device is described. The device includes at least one of a semiconductor transistor or a semiconductor diode. An optical detector is configured to detect light emitted by the at least one of the semiconductor transistor or the semiconductor diode during operation. A signal processor is configured to communicate with the optical detector to receive information regarding the light detected. The signal processor is further configured to provide information concerning at least one of an electrical current flowing in, a temperature of, or a condition of the at least one of the semiconductor transistor or the semiconductor diode during operation.

Abstract: An optically-monitored and/or optically-controlled electronic device is described. The device includes at least one of a semiconductor transistor or a semiconductor diode. An optical detector is configured to detect light emitted by the at least one of the semiconductor transistor or the semiconductor diode during operation. A signal processor is configured to communicate with the optical detector to receive information regarding the light detected. The signal processor is further configured to provide information concerning at least one of an electrical current flowing in, a temperature of, or a condition of the at least one of the semiconductor transistor or the semiconductor diode during operation.

Abstract: A pyramid-type multilevel converter for converting DC voltage to AC voltage waveforms, and vice versa. An example device can use modular building blocks to form a selector stage, a converter stage, and at least one intermediate stage if the number of converters within the converter stage is greater than or equal to 3, with the converter stage switching at high-frequency PWM to chop the DC voltages. The modular building blocks are connected in a symmetric or asymmetric pyramid configuration having a base of using the converter stage and an apex of the selector stage.

Abstract: A Modular Multilevel Converter (MMC) circuit for converting DC power to AC and vice versa. At each respective connection to the AC power-source/load, the MMC circuit uses one Pulse Width Modulation Insulated Gate Bipolar Transistor (PWM IGBT) to control the switching between upper and lower arms of sub-modules. The circuit eliminates the inter-phase inductors often used in MMCs, and replaces the inductors by two complementary-gated PWM IGBTs, thereby eliminating circulating current. Moreover, the multilevel converter topology disclosed herein requires less number of components including PWM IGBTs and capacitors. In fact, at least two submodules per-phase are eliminated: one submodule in the upper arm and one submodule in the lower arm. In other words, the MMC topology not only mitigates the circulating current but also eliminates at least one submodule in the upper arm and at least one submodule in the lower arm per-phase.

Abstract: An improved DC circuit breaker is provided for automatically detecting and isolating a fault between a source and a ground. The DC circuit breaker comprises at least one switch, in electrical series with a first inductor between the source and a load, and a second inductor magnetically coupled to the first inductor wherein a first side of the second inductor is electrically connected to the load and a second side of the second inductor is grounded through a capacitor.

Abstract: A pyramid-type multilevel converter for converting DC voltage to AC voltage waveforms, and vice versa. An example device can use modular building blocks to form a selector stage, a converter stage, and at least one intermediate stage if the number of converters within the converter stage is greater than or equal to 3, with the converter stage switching at high-frequency PWM to chop the DC voltages. The modular building blocks are connected in a symmetric or asymmetric pyramid configuration having a base of using the converter stage and an apex of the selector stage.

Abstract: A Modular Multilevel Converter (MMC) circuit for converting DC power to AC and vice versa. At each respective connection to the AC power-source/load, the MMC circuit uses one Pulse Width Modulation Insulated Gate Bipolar Transistor (PWM IGBT) to control the switching between upper and lower arms of sub-modules. The circuit eliminates the inter-phase inductors often used in MMCs, and replaces the inductors by two complementary-gated PWM IGBTs, thereby eliminating circulating current. Moreover, the multilevel converter topology disclosed herein requires less number of components including PWM IGBTs and capacitors. In fact, at least two submodules per-phase are eliminated: one submodule in the upper arm and one submodule in the lower arm. In other words, the MMC topology not only mitigates the circulating current but also eliminates at least one submodule in the upper arm and at least one submodule in the lower arm per-phase.

Abstract: An optically-monitored and/or optically-controlled electronic device is described. The device includes at least one of a semiconductor transistor or a semiconductor diode. An optical detector is configured to detect light emitted by the at least one of the semiconductor transistor or the semiconductor diode during operation. A signal processor is configured to communicate with the optical detector to receive information regarding the light detected. The signal processor is further configured to provide information concerning at least one of an electrical current flowing in, a temperature of, or a condition of the at least one of the semiconductor transistor or the semiconductor diode during operation.

Abstract: An improved DC circuit breaker is provided for automatically detecting and isolating a fault between a source and a ground. The DC circuit breaker comprises at least one switch, in electrical series with a first inductor between the source and a load, and a second inductor magnetically coupled to the first inductor wherein a first side of the second inductor is electrically connected to the load and a second side of the second inductor is grounded through a capacitor.

Abstract: An improved DC circuit breaker is provided for automatically detecting and isolating a fault between a source and a ground. The DC circuit breaker comprises at least one switch, in electrical series with a first inductor between the source and a load, and a second inductor magnetically coupled to the first inductor wherein a first side of the second inductor is electrically connected to the load and a second side of the second inductor is grounded through a capacitor.

Abstract: An unbalanced line-to-line current is injected at an injected frequency in a three-phase ac circuit. A first set of voltages and currents are obtained. A first set of transformed voltages and transformed currents are produced. The circuit is injected with a second unbalanced line-to-line current at a frequency linearly independent of the injected frequency. A second set of voltages and current are obtained. A second set of transformed voltages and transformed currents are produced The impedance of a source portion and a load portion of the circuit are calculated using the first and second set of transformed voltages, and the first and second set of transformed currents.

Abstract: An unbalanced line-to-line current is injected at an injected frequency in a three-phase ac circuit. A first set of voltages and currents are obtained. A first set of transformed voltages and transformed currents are produced. The circuit is injected with a second unbalanced line-to-line current at a frequency linearly independent of the injected frequency. A second set of voltages and current are obtained. A second set of transformed voltages and transformed currents are produced The impedance of a source portion and a load portion of the circuit are calculated using the first and second set of transformed voltages, and the first and second set of transformed currents.